Hammer-headed tool



May 26, 1925.

G. G. MITCHELL HAMMER HEADED TOOL Filed May 28, 1924 g h INVENT R.

{4 TTORNEYS.

Patented May 26, 1925.

nearer UNITED STATES PATENT OFFME,

GEORGE G. MITCHELL, 0F UNION, NEW JERSEY, ASSIGNOR T0 L. A. SAYRE COMPANY,

A OORPGBATIUN 0F IQEW JERSEY. V

HAMMEB-I-IEADED TOOL.

Application filed May 38, 1924. Serial No. 716,289.

,To all whom/it may concern:

Be it known that I, Gnoucn G. Mrrorrem, a citizen of the United States, and a resident of the town of Union, in the county'of Union and State of New Jersey, have invented new and useful Improvements inlIammer-Headed Tools, of which the following is a specification.

This invention relates in general to hatches, hammers and the like and more particularly to a novel and improved roughened or anti-slip driving face .for such tools utilized to prevent the tool from slipping or glancing off the head of a nail or the like I as the nail is being driven by the tool.

In the manufacture of, high grade heat treated or hardened steel hatchets, hammers and like percussion driving tools it is customary to test the heads thereof to determine the. degree hardness and locate fractures, etc, Such testing is commonly done by an, instrument known as arscleroscope which includes a haminerdike element which is caused to drop by action of gravity upon the article being, tested, the distance of rebound of the hammerof the scleroscope being an indication of the hardness of the steel of the tool being, tested. Where the tools to be tested, such as a hatchet or ahammer, have serratedor roughened faces of the known forms, for instance: a plurality of pyramidal points, or transverse ribs, it is impossible to test the tool from the center of the face, a smooth flat surface being necessary for utilization of; a scleroscope,as the hammer element of a scleroscope must strike a true square blow to properly register. Therefore, tools of the character-described are tested only from the sides of the head and should a fracture or imperfection be present at the center of the head it can-- not be located by a scleroscope and its presence is discovered only upon use of the tool when the head cracks or the face becomes fractured. a

The primary object of my invention is to provide a novel and improved roughened, serrated, anti-slip face for hatchets, hammers and the like, which permits the tool to be tested at the center of the face by a seleroscope and at the same time ensures against slipping or glancing off of the tool from a nail or the like while the nail is being driven.

Another object is to provide a tool of the character described having its facerso roughened as to form a small substantially fiat surface at the center of the face to permit testing thereof with a scleroscope.

Further objects are to provide such a tool having the rougl iened face of such a design as to permit the formation of said flat surface at the center of the hatchet simultaneously with the roughening oper ation and by the same machine; to provide a tool of the character described having a frusto-pyramidal projection at the center of the face which provides a small flat sur face, said projection being surrounded with a plurality of i pyramidal projections or points to form an anti-slip surface for said face, andto obtain other results and advantages as may be brought out by the following description.

Referring to the accompanying drawings,

, inwhich the same reference characters designate corresponding and like parts throughout the several views,

Figure l isa'side elevation ofa lathers hatchet having a hammer head embodying the invention FigureQ is an end elevation of the hatchet;

Figure 3 is a plan View of the face of jthe hammer head, and

Figured is a fragmentary transverse vertieal sectional view through thelhammer head.

For the purpose of illustrating the principles of the invention I have shown the same in connection with a latherls hatchet, but it :will be understood that} the invention is equally susceptible to use with hammers or other hammer headed tools. Specifically describing theembodiment of the, in vention illustrated, the reference character A designates the lathers hatchet formed with the usual cutting blade B; and hammer head G which is preferably rectangular in plan, as shown in Eigure 3. The head G of the hatchet and the face D thereof are subjected to heat treatment for the ,purpose of hardening the'same as is customary inthe manufacture of' high grade hardened steel tools. I

The face D ofthe head 0 is providedwith a plurality of series of grooves land 2 extending transversely of the face, the grooves of one of said series being arranged at right angles to the grooves of the other series, and the grooves of the respective series being so spaced and arranged as to form a substantially smooth and flat surface 3 at the center of the face and a plurality of projections t surrounding said smooth and flat surface to provide an anti-slip surface for the face D to prevent slipping or glancing off of the head from a nail or the like while the nail is being driven by the head. The smooth flat surface 3 is adapted to receive blows from a scleroscope to permit testing of the steel of the head C at the center thereof. With such a construction, it will be 'ob served that the head of the hatchet may be accurately tested for hardness on each of the four sides thereof and also the center, so that any fractures or imperfections in the steel throughout the head may be easily located.

Preferably, the grooves 1 and 2 are V- shaped and are so spaced and arranged as to provide two rows of chisel-shaped projections 5 arranged at right angles to each other and each disposed on a transverse center line of the face D, and the grooves 1 and 2 form a plurality of rows of smaller pyramidal projections 6 between the respective rows of the projections 5.

This particular arrangement of the grooves enables all of theprojections 5 and 6 and the surface 8 to be formed in one operation and with the same tool. The tool may be either a scoring tool which forms v the grooves while the head C is hot, or may be a milling cutter to form the grooves while the head is in a cold condition. Either the scorer or the miller, whichever is used, would be provided with a plurality of cutting teeth annularly. arranged correspondingly to the spacing of the grooves 1 and 2, the teeth being V-shaped to form the V-shaped'grooves. One series of grooves l or 2 is first formed by the scorer or the mill ing cutter, after which the head C is turned through an angle of 90 and the other series of grooves formed at rightangles to the first-mentioned series. It will be noted that the surface 3 forms the top of a substantially frusto-pyramidal projection and that the next adjacent projections 5 with the inclined sides provide ample clearance around the surface 3 to permit the hammer element of a scleroscope to accurately strike said surface.

The surface 3 is preferably disposed in the plane of the top of the projection t, and it will be observed that the invention permits of thorough testing of the material of the head of the tool, which would not be possible were the whole face D provided with pyramidal projections such as thoseindicated by the reference character 6, and fur thermore the adaptation of the face of the head to such testing does not decrease the anti-slipping effect thereof. While I have shown and described one form of roughened face for hammer heads, it will be understood that this is mainly for the purpose of illustrating the principles of the invention, and that other designs of roughened faces may be utilized without departing from the spirit or scope of the invention. Therefore I do not desire to be understood as limiting myself except as required by. the following claims when construed in the light of the prior art. 1

Having thus described the invention, what I claim is:

l. A tool having a hammer head formed of hardened steel and having a substantially smooth flat surface in its face within the edges thereof and surrounded by a plurality of intersecting grooves which form pointed projections at their intersections with each other, said flat surface serving to receive blows from a scleroscope to permit testing of the steel from the face of said head and said projections and grooves providing an anti-slip surface for said face.

2. A tool having a hammer head formed of hardened steel with a plurality of series of V-shaped transverse grooves in its face arranged at angles to each other, the innermost of said grooves forming at their intersections a smooth fiat surface at the center of said face and a plurality of pointed projections surrounding said flat surface, said flat surface serving to receive blows from a scleroscope to permit testing of the steel from the face of said head and said projections and grooves providing an anti-slip surface for said face.

3. A tool having a hammer head formed of hardened steel with two series of grooves in its face, the grooves of one series being disposed at right angles to the grooves of the other series, said grooves being so spaced and arranged as to form a plurality of rows of pyramidal projections and two rows of chisel-shaped projections at right angles to each other and each on a transverse center line of said face, a substantially smooth flat surface'being also provided at the center of said face by the intersection of said series of grooves, said projections providing an anti-slip surface for said face, and said flat surface serving to receive blows from a scleroscope to permit testing of the steel at the center of said head.

GEORGE G. MITCHELL. 

